BS DD CEN TS 12169-2008 Criteria for the assessment of conformity of a lot of sawn timber《大量锯材的合格评定准则》.pdf

1、DD CEN/TS12169:2008ICS 79.040NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWDRAFT FOR DEVELOPMENTCriteria for theassessment ofconformity of a lot ofsawn timberLicensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 09/10/2010 08:22, Uncontrolled Copy, (c) BSIThis Draft for Deve

2、lopment was published under the authority of the Standards Policy and Strategy Committee on 30 June 2010 BSI 2010ISBN 978 0 580 63519 9Amendments/corrigenda issued since publicationDate CommentsDD CEN/TS 12169:2008National forewordThis Draft for Development is the UK implementation of CEN/TS 12169:2

3、008. It supersedes DD ENV 12169:2000 which is withdrawn.This publication is not to be regarded as a British Standard.It is being issued in the Draft for Development series of publications and is of a provisional nature. It should be applied on this provisional basis, so that information and experien

4、ce of its practical application can be obtained.Comments arising from the use of this Draft for Development are requested so that UK experience can be reported to the international organization responsible for its conversion to an international standard. A review of this publication will be initiate

5、d not later than 3 years after its publication by the international organization so that a decision can be taken on its status. Notification of the start of the review period will be made in an announcement in the appropriate issue of Update Standards.According to the replies received by the end of

6、the review period, the responsible BSI Committee will decide whether to support the conversion into an international Standard, to extend the life of the Technical Specification or to withdraw it. Comments should be sent to the Secretary of the responsible BSI Technical Committee at British Standards

7、 House, 389 Chiswick High Road, London W4 4AL.The UK participation in its preparation was entrusted to Technical Committee B/543, Round and sawn timber.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all t

8、he necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 09/10/2010 08:22, Uncontrolled Copy, (c) BSIDD CEN/TS 12169:2008TECHNICAL S

9、PECIFICATIONSPCIFICATION TECHNIQUETECHNISCHE SPEZIFIKATIONCEN/TS 12169January 2008ICS 79.040 Supersedes ENV 12169:2000 English VersionCriteria for the assessment of conformity of a lot of sawn timberCritres de vrification de la conformit dun lot de bois sci Kriterien zur Konformittsprfung eines Lose

10、s SchnittholzThis Technical Specification (CEN/TS) was approved by CEN on 22 October 2007 for provisional application.The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit theircomments, particularly on the question

11、whether the CEN/TS can be converted into a European Standard.CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS availablepromptly at national level in an appropriate form. It is permissible to keep conflicting national standards in f

12、orce (in parallel to the CEN/TS)until the final decision about the possible conversion of the CEN/TS into an EN is reached.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland

13、, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1

14、050 Brussels 2008 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. CEN/TS 12169:2008: ELicensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 09/10/2010 08:22, Uncontrolled Copy, (c) BSIDD CEN/TS 12169:2008CEN/TS 12169:2008 (E) 2 Content

15、s Page Foreword3 Introduction .4 1 Scope 5 2 Normative references 5 3 Terms and definitions .5 4 Conformity control.6 4.1 Objective.6 4.2 Principle6 4.3 Applicable AQL 6 4.4 Type of inspection .6 5 Sampling.6 5.1 Sampling rules .6 5.2 Single procedure7 5.2.1 Single sampling .7 5.2.2 Double sampling9

16、 Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 09/10/2010 08:22, Uncontrolled Copy, (c) BSIDD CEN/TS 12169:2008CEN/TS 12169:2008 (E) 3 Foreword This document (CEN/TS 12169:2008) has been prepared by Technical Committee CEN/TC 175 “Round and sawn timber”, the secretariat of which is held by

17、AFNOR. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes ENV 12169:2000. According to the CEN/CENELEC Internal

18、Regulations, the national standards organizations of the following countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Ma

19、lta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 09/10/2010 08:22, Uncontrolled Copy, (c) BSIDD CEN/TS 12169:2008CEN/TS 12169:2008 (E) 4 Introduction The purpose of this

20、document is to define an inspection system for a lot of sawn timber. This document uses statistical sampling plans found in ISO 2859-1. Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 09/10/2010 08:22, Uncontrolled Copy, (c) BSIDD CEN/TS 12169:2008CEN/TS 12169:2008 (E) 5 1 Scope This document

21、 defines the sampling plans and procedures for inspection by attributes (measurable properties) of sawn timber lots exhibiting a homogenous distribution of characteristics. It also gives control regulations and conditions for conformity or non conformity of a lot in view of the agreed specification.

22、 This document applies to any sawn timber products claimed to comply with specifications defined in the sales contract. It does not cover the spread of different qualities within a grade or between the contracted grades. In case of a dispute, a sampling carried out only by customer or supplier is no

23、t valid as it cannot be guaranteed to be free from manipulation. Furthermore parties are free to enlarge the sampling or make use of another method provided an agreement is made between the interested parties. 2 Normative references The following referenced documents are indispensable for the applic

24、ation of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 2859-1, Sampling procedures for inspection by attributes Part 1: Sampling plans indexed by acceptable quality le

25、vel (AQL) for lot-by-lot inspection. 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 lot of sawn timber a number of sawn timber pieces of the same thickness and width and the same quality grade NOTE A lot of sawn timber can be, for example: p

26、ackage of sawn timber, truckload, a wagon load or shipload of sawn timber, pile of sawn timber, kiln load. 3.2 acceptable Quality Level (AQL) the maximum percentage of non-conforming pieces of sawn timber that can be considered satisfactory as a process average 3.3 non-conforming piece a piece which

27、 fails to meet the quality requirements 3.4 package a part of a homogeneous lot Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 09/10/2010 08:22, Uncontrolled Copy, (c) BSIDD CEN/TS 12169:2008CEN/TS 12169:2008 (E) 6 4 Conformity control 4.1 Objective The objective of the inspection is to dete

28、rmine with a high probability whether the lot does not conform to the specifications fixed in the contract and a complaint seems to be justified. Hence the decision is between “conformity“ and “nonconformity“. 4.2 Principle The control of the lot is carried out on the basis of attributes. The pieces

29、 making up the sample are defined as “conforming“ or “nonconforming“. The decision regarding conformity or nonconformity of the lot is made on the basis of the number of nonconforming pieces in comparison to the total number of the pieces in the sample. In the case of simultaneous assessments accord

30、ing to different specifications (e.g. appearance, moisture content, dimensions), the number of nonconforming pieces is evaluated independently. 4.3 Applicable AQL If no AQL value is defined in the accepted grading rules or in the contract, AQL 10 shall be used. (see Tables 2 and 3) NOTE If in random

31、 sampling the maximum number of nonconforming pieces “A“, as defined in the AQL tables is exceeded, the whole lot will contain, with a probability of more than 90 %, a percentage of nonconforming pieces in excess of the AQL value. 4.4 Type of inspection The inspection, described in this document, is

32、 carried out according to ISO 2859-1 (General inspection, normal inspection, reference to Table I, II or even III A). Other sampling plans, e.g. reduced or increased inspection, may be used if stipulated by the interested party in the contract or a separate agreement. 5 Sampling 5.1 Sampling rules S

33、ampling is based on the concept of AQL. AQL is generally suitable for trade agreements regarding conformity. Sampling shall be so that random, for none of the parties to the contract will be able to decide which pieces to be inspected. The minimum number of packages to be opened is shown in Table 1.

34、 If for any reason the number of packages given in the table is deemed insufficient (for example a large number of packages which are seen to be defective before they are opened), a larger number of packages may be opened. Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 09/10/2010 08:22, Unco

35、ntrolled Copy, (c) BSIDD CEN/TS 12169:2008CEN/TS 12169:2008 (E) 7 Table 1 Number of packages to be opened Number of packages in the lot Number of packages to be opened 1 2 to 5 6 to 11 12 or more 1 2 3 4a aIf these packages do not contain the number of pieces required in Table 2, the necessary addit

36、ional packages shall be opened. Sampling can be carried out either as single sampling (according to 5.2.1) or as double sampling (according to 5.2.2). Double sampling means that a smaller number of pieces than in simple sampling are inspected as a first sampling. This leads to “conformity“, “nonconf

37、ormity“ or “uncertain“. If result is “uncertain“, a second sampling is carried out and the results added to those of the first sampling. The conformity or nonconformity can be determined. The ways of wrapping and protection timber package during transport varies widely. Sometimes the top layer or pi

38、eces in the top layer are used to help protect the other pieces in the package. In such a case, the top layer may, by agreement, be excluded from the sampling. 5.2 Single procedure 5.2.1 Single sampling The number of packages to be opened is given in Table 1. Based on the number of pieces in the lot

39、, the total number of pieces to be inspected (sample size) is given in Table 2. By dividing the sample size by the number of packages to be opened, determine the number of test pieces per package, rounding the result down to the nearest whole number. If the total number of pieces, as calculated, doe

40、s not agree exactly with the number given in Table 2, the extra piece(s) has (have) to be selected at random in opened packages (only one per package). The first piece to be assessed in each package is selected at random in the top layer. Then, each layer is scanned from left to right according to a

41、 frequency of inspection obtained by dividing the total number of pieces in the package by the number of pieces to be inspected ; the result is round down to the nearest whole number. The number of nonconforming pieces in different packages is cumulated. The Column A of Table 2 allows to determine t

42、he conformity of the lot. EXAMPLE An example is given in Figure 1, where a lot consisting of 3 600 pieces in 15 packages is inspected. Therefore, in accordance with Table 1, four packages are opened. In accordance with Table 2, AQL 10, 125 pieces are inspected or 31 pieces per package (which makes 1

43、24 pieces, so take an extra piece at random from one of the packages). As there are 240 pieces in each package, every eighth piece is inspected (240/31, rounded). In Figure 1, every eighth piece gave 30 pieces, so one extra piece is selected at random. If out of the 125 sample pieces more than 21 ar

44、e nonconforming (see Table 2) the lot is nonconforming. Otherwise the lot is conforming. Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 09/10/2010 08:22, Uncontrolled Copy, (c) BSIDD CEN/TS 12169:2008CEN/TS 12169:2008 (E) 8 Figure 1 Selecting pieces in a package Key 1) First piece selected a

45、t random 2) Extra piece to reach the requested number Table 2 Single sampling - Sample sizes and maximum numbers of nonconforming pieces Pieces in the lot AQL 4 AQL 6,5 AQL 10 S A S A S A 100 to 150 151 to 280 281 to 500 501 to 1200 1201 to 3200 3201 to 10000 10001 to more 20 32 50 80 125 200 315 2

46、3 5 7 10 14 21 20 32 50 80 125 200 200 3 5 7 10 14 21 21 20 32 50 80 125 125 125 5 7 10 14 21 21 21 S = Sample size A = Maximum number of nonconforming pieces Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 09/10/2010 08:22, Uncontrolled Copy, (c) BSIDD CEN/TS 12169:2008CEN/TS 12169:2008 (E)

47、9 5.2.2 Double sampling Determine the number of packages to be opened from Table 1. Based on the number of pieces in the lot, determine the total number of pieces to be inspected in the first and second inspections (sample size) by using Table 3, the lines marked “Total“. Carry out the second inspec

48、tion on a sample taken by the same method as the first. By dividing the sample size by the number of packages to be opened, determine the number of test pieces per package, the result being down to the nearest whole number. If the total number of pieces, as calculated, does not agree exactly with th

49、e number given in Table 3, the extra piece(s) has (have) to be selected at random in opened packages (only one per package). The first piece to be assessed in each package is selected at random in the top layer. Then, each layer is scanned from left to right according to a frequency of inspection obtained by dividing the total number of pieces in the package by the number of pieces to be inspected; the result is round down to the nearest whole number. The number of nonconforming pieces in different packages is cumulated. The Column A of Table 3 allows to d